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Chelsea Therapeutics International, Ltd., the manufacturer of an experimental treatment called droxidopa (Northera™), announced this week that an advisory committee to the US Food and Drug Administration (FDA) is recommending that the drug be approved to treat a form of low blood pressure affecting people with certain conditions including Parkinson's disease. The condition is called neurogenic orthostatic hypotension (NOH).

Neurogenic orthostatic hypotension is a sharp drop in blood pressure that occurs when a person gets up from bed or from a chair, and it is caused by a failure of the peripheral nervous system. It can cause dizziness, falls or even loss of consciousness. Currently, no effective treatment options exist to ease its symptoms.

Chelsea Therapeutics first submitted an application to the FDA requesting that Northera be approved to treat NOH in 2011. In 2012, the FDA’s advisory committee recommended that the drug be approved, but the FDA rejected the application, asking for more data. This week, the FDA’s advisory committee voted 16 to 1, to again recommend that the FDA approve the drug.

With this recommendation in hand, the FDA will review all evidence before making its final decision. PDF will keep the community posted as any additional news becomes available.

Richard Hoffmann, Pharm.D., a PDF Research Advocate who served on the FDA’s advisory committee commented, “I was proud to represent the Parkinson’s disease community within the FDA's new drug approval process for Northera. Along with my fellow 200 Research Advocates, I commend the FDA for engaging patients throughout the process. Our committee reviewed extensive feedback from patients – including letters from approximately 50 patients and oral testimony from 20 patients – many of whom live with Parkinson’s disease. Their perspectives proved invaluable to reviewers in making our final recommendation about the future Northera.”

James Beck, Ph.D., PDF’s Vice President, Scientific Affairs, added, “Neurogenic orthostatic hypotension is a serious condition that affects many people with Parkinson’s disease and its consequences, if left untreated, can be deadly. That is the crux – no good treatment options exist. Although questions remain about Northera's long term effectiveness, in the two years that have passed since the FDA first considered Northera, additional data has shifted the opinion of the advisory committee from a split decision to one overwhelmingly in favor of approval.”

See full announcement below, as reported by Reuters and contact PDF's HelpLine for further information at (800) 457-6676 or info@pdf.org.

FDA advisory panel backs Chelsea Therapeutics drug

BY TONI CLARKE

WASHINGTON Tue Jan 14, 2014 6:26pm EST

(Reuters) - A drug to treat a rare form of low blood pressure made by Chelsea Therapeutics International Ltd is effective enough to warrant regulatory approval, an advisory panel to the U.S. Food and Drug Administration concluded on Tuesday.

The panel voted 16 to 1 in favor of the drug, Northera, for patients with neurogenic orthostatic hypotension (NOH), a rare, chronic type of low blood pressure that occurs on standing and is associated with certain neurological disorders such as Parkinson's disease.

Chelsea shares more than doubled in after-hours trading. The FDA is not bound to follow the advice of its panels but typically does so.

Panelists wrestled with gaps in the clinical data which they said made it difficult to determine whether the drug, which appears effective after one week's treatment, is effective over the long term. Most suggested the company be required to conduct a follow-up study to prove a durable benefit.

Dr. James de Lemos, a cardiologist and professor of medicine at the University of Texas Southwestern Medical Center, said he voted in favor "based on the compelling evidence of suffering and the absence of viable alternatives," but said the approval should be conditional on further study.

Patients and patient advocates testified before the panel about the positive impact the drug has had on their lives.

Gail Hershkowitz, 65, a retired music teacher who lives in Boynton Beach, Florida, was diagnosed with Parkinson's disease 15 years ago and, later, with NOH. She said in an interview that she became afraid to leave her house after fainting and vomiting multiple times in public. She took Northera as part of a clinical trial and says it has enabled her to lead a relatively normal life.

But some panelists expressed frustration that the experience of patients who have benefited from the drug was not clearly backed up by data from the clinical trials.

A reviewer for the FDA, Dr. Shari Targum, said in preparatory documents published on Friday that she did not think the data was strong enough to support approval.

Chelsea's shares fell as much as 36 percent following that review. They were halted during the panel meeting on Tuesday, and rose to $5.78 in after-hours trading from a close on Monday of $2.30.

Northera, also known as droxidopa, is converted by the body into norepinephrine, a chemical messenger that sends signals to blood vessels and the heart to regulate blood pressure. Insufficient norepinephrine can lead to light-headedness and fainting upon standing.

Chelsea originally filed for approval of droxidopa in 2011, based on a study known as 301. In February, 2012, an FDA advisory panel recommended approval of the drug, but the agency rejected it and asked for additional data.

The company sought to address the FDA's concerns using data from a different study known as 306B, but the FDA denied the request and said an additional trial would be needed.

Chelsea appealed the decision, and in early 2013 the FDA agreed to accept a resubmission based on data from the 306B study, saying that while short-term data, if convincing, would be adequate for approval, a post-approval study could be required to prove the results were durable.

Targum said the results of study 306B did not meet those criteria. Most panelists, however, said that while there was no convincing evidence that the drug provides a durable benefit, there was no convincing evidence to show that it does not show a benefit.

"This is a terrible disease and there are no other effective medications," said Dr. Vasilios Papademetriou, a cardiologist and professor of medicine at Georgetown University. Although the studies were not perfect, he said, "the data convinced me there is a long lasting benefit in some patients."

Chelsea licensed rights to the drug outside Asia from Dainippon Sumitomo Pharma in 2006. It was introduced in Japan in 1989.

(Reporting by Toni Clarke in Washington. Editing by Andre Grenon and David Gregorio)